Efficient capture of lead ion and methylene blue by functionalized biomass carbon-based adsorbent for wastewater treatment

In this paper, a new type of polyacrylic acid grafted lignosulfonate (SLS)/ carboxymethyl cellulose (CMC) and biochar (BC) composites (SLS/CMC/BC) were prepared by free radical polymerization, which can effectively adsorb Pb2+ and methylene blue (MB). In monopollutant system, the maximum adsorption capacity for Pb2+ and MB can reach 204 mg g−1 and 113 mg g−1. Another finding is that the presence of Pb2+ in the mixed system basically had no effect on the adsorption of MB, while the adsorption of Pb2+ by the adsorbent was significantly enhanced under the promotion of MB. The analysis shows that electrostatic attraction and complexation play a key role in the removal of pollutants. Also, the results of the regeneration capacity test and the stability test clearly show that the adsorption capacity of SLS/CMC/BC to target pollutants has not been significantly weakened after five adsorption-desorption processes, which indicates that the adsorbent is a promising material in the field of adsorption.